How to automate copy of Total Planned Cost value to Total Forecast?

Dear all,

do you think this is possible?

Total Planned cost comes from work plan. Total Forecast is now calculated from staffing profile, but business need is, that it will be only simple copy of Total Planned Cost. I know that I can edit forecast manually in the Financial Summary, so I can have these values the same, but how to make that automaticcaly without need to edit the Financial Summary?